We strongly reject, therefore, every explanation of the death of Christ which does not have at it's centre 'satisfaction through substitution' indeed divine self satisfaction through divine self substitution. The cross was not a commercial bargain with the devil, let alone one which tricked and trapped him, nor an exact equivalent, a quid pro quo to satisfy a code of honour or technical point of law, nor a compulsory submission to God to some moral authority above Him from which He could not otherwise escape, nor a punishment of a meek Christ through a harsh and punitive Father, nor a procurement of salvation by a loving Christ from a mean and reluctant Father, nor an action by which the Father bypassed Christ as mediator.
Instead the righteous, loving Father humbled Himself to become in and through His only Son, flesh, sin and a curse for us, in order to redeem us without compromising His own character. The theological words 'satisfaction' and 'substitution' need to be carefully defined and safeguarded, but they can not, under any circumstances by given up. The Biblical Gospel of atonement is of God satisfying Himself by substituting Himself for us.
John Stott, The Cross Of Christ, Pp 159-160
If you've not yet read 'The Cross of Christ' run, don't walk to your nearest bookshop and grab a copy. It's clear, it's helpful, it's heart warming. It may be the most vital book you'll ever read. Increasingly as i go through it, and as i read the Bible, i think that a defective view of the atonement leads to a defective view of God, and vice versa. If Christ death was about bearing our pain, or offering a perfect confession of our sin, we've lost the holiness of God. A holy God demands satisfaction for our sin, not someone to suffer so we know how bad it is. In and through Jesus, God became just and the justifier of the one who has faith in Christ.
Secondly, it may be fed by a poor Biblical Theology, a poor understanding of how the Old Testament is a Christian book. Read Leviticus...why are those sheep being killed? So they can empathise with us? To show us the worst excess of our sin? By way of example? They are being killed, like Christ our passover lamb was, to show that without the shedding of blood there is no forgiveness of sin, that God, rightly, demands a bloody sacrifice to pay for our sins. This is not a primitive, base understanding of crime and punishment, this is not an pagan idea grafted onto Christianity...this is justice, humbling, sacrificial substitutional justice, which is probably why we dislike it so much...